Rapid evolution drives ecological dynamics in a predator–prey system

Ecological and evolutionary dynamics can occur on similar timescales. However, theoretical predictions of how rapid evolution can affect ecological dynamics are inconclusive and often depend on untested model assumptions. Here we report that rapid prey evolution in response to oscillating predator density affects predator–prey (rotifer–algal) cycles in laboratory microcosms. Our experiments tested explicit predictions from a model for our system that allows prey evolution. We verified the predicted existence of an evolutionary tradeoff between algal competitive ability and defence against consumption, and examined its effects on cycle dynamics by manipulating the evolutionary potential of the prey population. Single-clone algal cultures (lacking genetic variability) produced short cycle periods and typical quarter-period phase lags between prey and predator densities, whereas multi-clonal (genetically variable) algal cultures produced long cycles with prey and predator densities nearly out of phase, exactly as predicted. These results confirm that prey evolution can substantially alter predator–prey dynamics, and therefore that attempts to understand population oscillations in nature cannot neglect potential effects from ongoing rapid evolution.

[1]  U. Halbach,et al.  Quantitative relations between phytoplankton and the population dynamics of the rotifer Brachionus calyciflorus Pallas Results of laboratory experiments and field studies , 1974 .

[2]  J. Pickett-Heaps.  Green algae: Structure, reproduction, and evolution in selected genera , 1975 .

[3]  Green Algae. Structure, Reproduction and Evolution in Selected Genera , 1976 .

[4]  G. Kraepelin.  J. PICKETT‐HEAPS, Green Algae. Structure, Reproduction and Evolution in Selected Genera. 606 S., 44 Strichzeichnungen, 882 Mikroaufnahmen. Sunderland, Mass. 1975. Sinauer Associates, Inc. Pbl./W. H. Freeman & Co. $ 23.40 , 1977 .

[5]  Jacques Monod,et al.  LA TECHNIQUE DE CULTURE CONTINUE THÉORIE ET APPLICATIONS , 1978 .

[6]  D. Geary.  Evolution and Escalation: An Ecological History of Life, Geerat J. Vermeij. Princeton University Press, Princeton (1987), xv, +527. Price $47.50 , 1988 .

[7]  R. Tollrian,et al.  The Ecology and Evolution of Inducible Defenses , 1990, The Quarterly Review of Biology.

[8]  G. Vermeij.  THE EVOLUTIONARY INTERACTION AMONG SPECIES: Selection, Escalation, and Coevolution , 1994 .

[9]  K. Rothhaupt.  Algal nutrient limitation affects rotifer growth rate but not ingestion rate , 1995 .

[10]  Ross Ihaka,et al.  Gentleman R: R: A language for data analysis and graphics , 1996 .

[11]  R. Hilborn,et al.  The Ecological Detective: Confronting Models with Data , 1997 .

[12]  D. Post,et al.  Lake ecosystems: Rapid evolution revealed by dormant eggs , 1999, Nature.

[13]  William W. Murdoch,et al.  Large-amplitude cycles of Daphnia and its algal prey in enriched environments , 1999, Nature.

[14]  B. Kendall,et al.  WHY DO POPULATIONS CYCLE? A SYNTHESIS OF STATISTICAL AND MECHANISTIC MODELING APPROACHES , 1999 .

[15]  S. Ellner,et al.  Crossing the hopf bifurcation in a live predator-prey system. , 2000, Science.

[16]  P. Abrams.  The Evolution of Predator-Prey Interactions: Theory and Evidence , 2000 .

[17]  B. Sinervo,et al.  Density cycles and an offspring quantity and quality game driven by natural selection , 2000, Nature.

[18]  R. Lenski,et al.  Linking genetic change to community evolution: insights from studies of bacteria and bacteriophage , 2000 .

[19]  T. Quinn,et al.  Rapid evolution of reproductive isolation in the wild: evidence from introduced salmon. , 2000, Science.

[20]  R. Huey,et al.  Rapid evolution of a geographic cline in size in an introduced fly. , 2000, Science.

[21]  F. Keesing,et al.  Frontiers of Ecology , 2001 .

[22]  S. Palumbi.  The Evolution Explosion: How Humans Cause Rapid Evolutionary Change , 2001 .

[23]  Alan A. Berryman,et al.  Population cycles : the case for trophic interactions , 2002 .

[24]  S. Ellner,et al.  Predator–prey cycles in an aquatic microcosm: testing hypotheses of mechanism , 2002 .

[25]  B. Kendall,et al.  DYNAMICAL EFFECTS OF PLANT QUALITY AND PARASITISM ON POPULATION CYCLES OF LARCH BUDMOTH , 2003 .

[26]  M. Holyoak,et al.  Complex Population Dynamics: A Theoretical/Empirical Synthesis , 2003 .